DETECTION OF GLYPHOSATE-RESISTANT PALMER AMARANTH (Amaranthus palmeri) IN AGRICULTURAL AREAS OF MATO GROSSO, BRAZIL

Planta Daninha

AGROCON Assessoria Agronômica Ltda, Santa Bárbara d'Oeste, Brasil¹  LÓPEZ-OVEJERO, R. F.¹  Monsanto do Brasil, São Paulo, Brasil¹  NICOLAI, M.¹  CARVALHO, S. J. P.¹  IFSULDEMINAS, Machado, Brasil¹  USP, Piracicaba, Brasil¹  CAVENAGHI, A. L.¹  CHRISTOFFOLETI, P. J.¹  Centro Universitário de Várzea Grande, Várzea Grande, Brasil¹  GONÇALVES NETTO, A.¹ 

关键词: pigweeds;    susceptibility;    dose-response;    management;    control;   

DOI  :  10.1590/S0100-83582015000300020

学科分类：农业科学（综合）

来源: Sociedade Brasileira da Ciencia das Plantas Daninhas (S B C P D) / Brazilian Society of Herb Science

【 摘 要 】

The recent introduction of Palmer amaranth (Amaranthus palmeri) in Brazilian agricultural areas may promote several changes on weed management, especially in no-till systems and in glyphosate-resistant crops, since glyphosate-resistant biotypes of A. palmeri have been frequently selected in other countries. Therefore, this research was developed in order to evaluate the glyphosate susceptibility of a Palmer amaranth biotype recently identified in the State of Mato Grosso, Brazil. For this purpose, glyphosate susceptibility of three Amaranthus biotypes was compared: A. hybridus var. patulus, collected in the State of Rio Grande do Sul - Brazil; A. hybridus var. patulus, collected in the State of São Paulo - Brazil; and A. palmeri, collected in the State of Mato Grosso - Brazil. Dose-response curves were generated for all biotypes, considering eight rates of glyphosate and six replicates. All the experiments were repeated twice. Both A. hybridus biotypes were satisfactorily controlled by glyphosate, demanding rates equal to or lower than 541.15 g a.e. ha-1 for 80% control (LD80). The A. palmeri biotype was not controlled by glyphosate in any of the assessments and required rates greater than 4,500 g a.e. ha-1 to reach LD80, which are economically and environmentally unacceptable. Comparison of the Brazilian A. palmeri biotype to the A. hybridus biotypes, as well as, to the results available in scientific international literature, led to the conclusion that the Brazilian Palmer amaranth biotype is resistant to glyphosate.

【 授权许可】

Unknown